Field of the Invention
The present invention relates to a method of inspecting a cutting blade to examine whether or not the abrasive grains on the cutting edge of the cutting blade have proper selected particle diameters.
Description of the Related Art
Cutting apparatus provided with cutting blades are used to divide semiconductor wafers with a plurality of semiconductor devices formed on their surfaces, optical device wafers with optical devices thereon, glass substrates, ceramics substrates, and resin substrates, etc. into individual device chips. The cutting edge of the cutting blade for use on cutting apparatus is formed of abrasive grains of diamond or the like that are bound by plating or a bonding material of metal, resin, or the like. As the cutting blade cuts a workpiece, the cutting edge self-sharpens to enable the abrasive grains to break and cut the workpiece with a certain level of sharpness.
Since chipping correlates with the abrasive grain diameter, a cutting blade having abrasive grains whose average particle diameters are smaller than a predetermined size is selected in order to cut a workpiece with chips kept below a predetermined size. Inasmuch as the types of cutting blades are classified according to abrasive grain diameters and bonding materials, a cutting blade is selected on the basis of the results of machining processes which are determined using a number of cutting blade types. Cutting blades whose types are divided according to abrasive grain diameters on the order of μm make it impossible to tell the difference between their abrasive grain diameters by appearance. For this reason, it is customary for the operator to confirm the type of a cutting blade using as a clue a mark or the like that its manufacturer has applied to the cutting blade, and install the confirmed cutting blade on the spindle (see, for example, Japanese Patent Laid-Open No. 2009-83016).